Target modeling, antenna array design and conventional beamforming algorithms for radar target DOA estimation

Collision avoidance systems for Unmanned Aerial Vehicle (UAV) use ultrasonic or radio wave radar equipment, for target detection. In direction-of-arrival (DOA) antenna array estimation, the direction of a signal is usually assumed to be a point. The article analyze the Uniform Linear Array(ULA) and Minimum Redundancy Array (MRA) beamforming arrays taken into account the mutual coupling between the antenna array elements. Simulation is performed for real antenna arrays and is shown that the sidelobe level is increasing for each array but for MRA the symmetry also distorted. Therefore for adaptive antenna applications is especially important the compensation of mutual coupling of antennas. Conventional beamformer (BF), Capon (CP), MUSIC and sample matrix inversion (SMI) based on particle filter are investigated and compared. In this paper, we consider aerial vehicle backscatter using ray tracing method and DOA estimation when the signal sources are distributed. Model for distributed source is proposed, and estimation methods are considered under this models.